“There’s definitely momentum behind it,” MacLeary says. “Whether that momentum has pushed it over the tipping point, I don’t know. It reminds me of my experience in early Twitter, which was very positive. You felt like you knew everyone there.” Whether Mastodon stays a nice, utopian “early Twitter” or becomes a ubiquitous, messy social network is yet to be seen. But it’s growing in its potential to replicate some of what Twitter does, with politicians, celebrities, and journalists signing up. Twitter profiles now often bear Mastodon usernames, as social groups make the move to the other app. But there’s a schism: Some new users want Mastodon to be Twitter, and some Mastodon users are there because they’re over Twitter. And with that growing number of users comes more responsibility—not just for Mastodon itself, but for volunteer administrators, whose hobbies running servers have become second jobs. “There are a lot of people who really don’t realize what they’re getting themselves into,” says Corey Silverstein, an attorney who specializes in internet law. “If you’re running these [instances], you have to run it like you’re the owner of Twitter. What people don’t understand is how complicated it is to run a platform like this and how expensive it is.” Because Mastodon is decentralized, it relies on various server administrators instead of one central hub to stay online. These admins aren’t just glorified users; they become more like internet service providers themselves, says Silverstein, and thereby responsible for keeping their servers compliant with copyright and privacy laws. If they fail, they could be on the hook for lawsuits. And they must follow complex legal frameworks around the world. “I worry that people will not want to host instances at all, because they go, ‘this is too scary,’” says Corynne McSherry, legal director at the Electronic Frontier Foundation, a nonprofit focused on civil liberties in the digital world. “But it doesn’t have to be scary.” Eugen Rochko, the founder of Mastodon, did not respond to an email with questions about Mastodon’s legal responsibility for content posted to the instances using its open source software. MacLeary says server administrators are vulnerable in a few ways—to harassment from users who don’t like their decisions, and to legal issues. MacLeary is still learning about the various laws that could affect mas.to and has already made clear rules against discrimination and harassment. Mas.to also bans content that is illegal in the United Kingdom (where MacLeary lives) and Germany (where the servers are hosted). “We’ve learned what rules to put in place over time,” says MacLeary. “There are rules in there that I wouldn’t have thought of. It’s a constant education piece.” These are growing pains that startup social networks are accustomed to, but they have had different goals than Mastodon—chief among them: make money. Twitter’s intent is to grow and profit, whereas Mastodon did not launch with such ambitions. Twitter and Mastodon are not twins, and they sit far apart in capitalist identity. But they are inextricably tied: As Twitter stumbles, Mastodon surges. Twitter had a major uptick in popularity after appearing at SXSW in 2006. But it became ubiquitous and unignorable after the role it played during the Arab Spring, which began in late 2010, in helping protesters organize and disseminate breaking news around the world. The bird app proved powerful beyond its creators’ and investors’ expectations. And it became part of the mainstream news cycle as celebrities and politicians used it to make their own announcements. Barack Obama, for example, took to Twitter to announce he had won his reelection bid for US president in 2012. The tweet circulated through print and broadcast media. People fear losing Twitter for both valuable news information and the spectacle that comes with it. Mastodon isn’t there—yet. But it did become a go-to place for journalists suspended by Musk last week. Muira McCammon, a doctoral candidate in the Annenberg School for Communication at the University of Pennsylvania who has researched social platform death, says Mastodon is currently less performance and more “negotiation and confusion” around its purpose and evolution, which may prove less enticing for some. People may be spending more time on other networks or trying them out, but it’s soon to say if they will fill Twitter’s void. “It’s a natural tendency for people to go elsewhere online to try to find a replica of Twitter,” McCammon says. “But Mastodon is not Twitter. It is not built like Twitter. And it is not aiming to churn a profit. So there is undoubtedly going to be friction that arises in that moment of migration.”